Caesar (title)

Caesar (English pl. Caesars; Latin pl. Caesares) is a title of imperial character. It derives from the cognomen of Julius Caesar, the Roman dictator. The change from being a familial name to a title adopted by the Roman Emperors can be dated to about AD 68/69, the so-called "Year of the Four Emperors".

For political and personal reasons Octavian chose to emphasize his relationship with Caesar by styling himself simply "Imperator Caesar" (whereto the Roman Senate added the honorific Augustus, "Majestic" or "Venerable," in 27 BC), without any of the other elements of his full name. His successor as emperor, his stepson Tiberius, also bore the name as a matter of course; born Tiberius Claudius Nero, he was adopted by Caesar Augustus on June 26, 4 AD, as "Tiberius Julius Caesar." The precedent was set: the Emperor designated his successor by adopting him and giving him the name "Caesar."

The fourth Emperor, Claudius, was the first to assume the name "Caesar" upon accession, without having been adopted by the previous emperor; however, he was at least a member by blood of the Julio-Claudian dynasty, being the maternal great-nephew of Augustus on his mother's side, the nephew of Tiberius, and the uncle of Caligula. Claudius in turn adopted his stepson and grand-nephew Lucius Domitius Ahenobarbus, giving him the name "Caesar" in the traditional way; his stepson would rule as the Emperor Nero. The first emperor to assume the position and the name simultaneously without any real claim to either was the usurper Servius Sulpicius Galba, who took the imperial throne under the name "Servius Galba Imperator Caesar" following the death of the last of the Julio-Claudians, Nero, in 68. Galba helped solidify "Caesar" as the title of the designated heir by giving it to his own adopted heir, Lucius Calpurnius Piso Frugi Licinianus.

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